* {
    margin: 0;
    padding: 0;
}

#initialization {
    height: 10%;
    margin: 0 auto;
    text-align: center;
}

#initialization p {
    padding: 5px 0;
}

#btn-wrapper {
    height: 5%;
    text-align: center;
    margin-bottom: 5px;
}

#btn-wrapper button {
    padding: 0 3px;
    margin: 0 15px;
}

#maze {
    margin: 5px auto;
}

#maze::after {
    content: '';
    display: block;
    clear: both;
}

#maze .block {
    width: 10px;
    height: 10px;
    box-sizing: border-box;
    float: left;
}

#maze .in {
    background-color: green;
}

#maze .out {
    background-color: red;
}

#maze .road {
    background-color: #fff;
}

#maze .wall {
    background-color: #333;
}

.tips {
    display: none;
    height: 50px;
    text-align: center;
    margin: 0 auto;
    color: red;
}